As a conventional core for a wire-wound electronic component, a core for a common mode choke coil disclosed by Japanese Patent Laid-Open Publication No. H11-204346 is known. Such a core has flanges at both ends of a winding base, and each of the flanges is divided into two parts by a groove extending in a direction in which the winding base extends. External electrodes are provided on the respective parts of the flanges.
A wire wound around the core crosses the grooves while extending from the winding base to the external electrodes. Therefore, the parts of the wire crossing the grooves do not contact with the core and float in the air. Therefore, when a common mode choke coil using the core is mounted on a circuit board, if a foreign object is stuck between either of the flanges and the circuit board, the part of the wire crossing the groove will be pushed toward the bottom of the groove, which may cause wire disconnection.